Antioxidant compositions and methods thereto

ABSTRACT

The present invention provides a performance assay that measures the total antioxidant activity of a composition using oxygen uptake in contrast to prior art methods that measure antioxidant capacity by indirectly measuring degradation of a fluorescent compound by following the disappearance of fluorescence. Using the performance antioxidant assay of the present invention, an antioxidant composition having synergistic activity is provided by the present inventors that includes flavonoids such as the flavonol quercetin, mixed tocopherols or tocotrienols, grape skin extract, green tea extract and bush plum. The antioxidant activity of the present composition exceeds 6,000 micromoles Trolox equivalent units per gram using the present invention.

FIELD OF THE INVENTION

The present invention relates to the field of measuring antioxidantactivity of a composition including both lipophilic and hydrophilicantioxidants in a single assay. The present invention also relates toantioxidant compositions having a synergistic antioxidant activity, thecompositions comprising water soluble and lipid soluble ingredients.Further, a method of screening antioxidant preparations for antioxidantcapacity is provided.

BACKGROUND OF THE INVENTION

Biological systems have developed antioxidant systems to combat theeffects of radicals and other pro-oxidative species. An antioxidant isany substance that significantly delays or prevents oxidation of anoxidizable substrate. Certain enzymes are antioxidants such assuperoxide dismutase and catalase, which are coded for by manyorganisms. Substances such as vitamin C and plant phenols areantioxidants introduced through the diet into biological systems. It hasbeen proposed that naturally occurring levels of these substances arenot adequately produced in the body or ingested in the normal diet. Thenormal diet often does not provide enough antioxidants because it isdeficient in fruits and vegetables. Further, fruits and vegetables thatare in the diet are likely depleted of their antioxidants due tomodem-day processing. The normal diet could be improved, but taking intoaccount today's lifestyles and poor composition of Western foods manychoose to supplement their normal diet with antioxidants.

While a tremendous amount of research has gone into use of antioxidantsas nutritional supplements, supplementation of the modem diet has notbeen consistently successful (European Research on Functional Effects ofDietary Antioxidants, Sept. 25-28, 2002, Cambridge, UK). Problems withaccurately and consistently measuring antioxidant capacity under variousconditions and of measuring compositions having varying amounts oflipophilic versus hydrophilic ingredients have not been solved.

Several laboratory methods have been developed to determine the abilityof a substance to quench a free radical or to determine its antioxidantcapacity. For a review, see Halliwell B., and Gutteridge J. M. C., FreeRadicals in Biology and Medicine. 3rd Edition. New York: OxfordUniversity Press, 2000. These assays are the TEAC, ¹⁹F-NMR, TRAP,modified TRAP, FRAP, the Glazer fluorescence-based method, thephosphomolybdenum complex method, and the ORAC, all of which areproposed to measure some aspect of a substance's ability to quench freeradical species.

Prior ORAC assays for antioxidant capacity rely on the generation of aradical that oxidizes a substrate. In the presence of an antioxidant,the oxidation of the substrate is slowed. The protective effect of anantioxidant is measured by determining the area under a decay curve(AUC) of the test sample as compared to a blank. A method called oxygenradical absorbance capacity (ORAC (β-PE)) measures antioxidant activityagainst peroxyl radical induced by 2,2′-azobis(2-amidinopropane)dihydrochloride (AAPH) at 37° C. β-phycoerythrin (β-PE) was used inthese assays as a fluorescent probe where loss of fluorescence of β-PEis an indication of the extent of damage from its reaction with aperoxyl radical.

Several drawbacks of using β-PE as a probe led Ou et al. (J Agric FoodChem. 2001;49(10):4619-4626) to develop an assay using fluorescein asthe fluorescent probe (ORAC (fl)). However, the fluorescein system doesnot measure antioxidant capacity of lipophilic samples since the assayis performed in aqueous solution. A modification of the ORAC (fl) methodwas described by Huang et al. (J Agric Food Chem. 2002;50(7):1815-1821)for lipophilic antioxidants using randomly methylated beta-cyclodextrinas a solubility enhancer. The reaction mechanism was determined to bethat of hydrogen atom transfer. The ORAC (fl) method usingbeta-cyclodextrin does not measure antioxidant activity of carotenoidsand polyunsaturated fatty acids since carotenoids and fatty acids arenot chain-breaking antioxidants (Huang et al. ibid). These antioxidantsmay act as singlet oxygen scavengers and may follow a different reactionmechanism. The ORAC (fl) method has been accepted by the industry as thegold standard for measuring antioxidant capacity.

U.S. published patent application 2002/0182736 to Aldini et al.describes a method that is alleged to determine the total antioxidantactivity of a sample in both lipid and aqueous compartments. The sampleis incubated with a lipophilic radical generator and an oxidizablelipophilic indicator in a lipid compartment of the sample. Oxidation ofthe oxidizable lipophilic indicator provides a measure of theantioxidant activity of the lipid compartment of the sample. The sampleis also incubated with a hydrophilic radical generator and an oxidizablehydrophilic indicator in an aqueous compartment of the sample. Oxidationof the oxidizable hydrophilic indicator provides a measure of theantioxidant activity of the aqueous compartment of the sample. HPLC andfluorescence assays were used to determine these separate values.

The present inventors observed that assays using the ORAC (fl) provideddata that showed an increase in fluorescence after addition of theradical initiator. The ORAC (fl) relies on the assumption thatfluorescein is the only fluorescent component being measured. In fact,any molecule having absorbance, fluorescence or phosphorescence at thewavelength measured in the ORAC (fl) contributes to the values obtainedfrom this assay. Further, such measured absorbance, fluorescence, orphosphorescence may not be related to antioxidant capacity asdemonstrated by initial rise in fluorescence values. Therefore, anycompound in a complex sample that fluoresces at the same wavelength asfluorescein will also be measured causing a skewed result.

Oxygen uptake has been previously used as a measure of antioxidantactivity. The discovery that aqueous dispersions of oxidizable organiccompounds can be readily and reproducibly initiated at a constant rate,R_(i), by peroxidation using the water-soluble azo compound2,2′-azo-bis-(2-amidipropane hydrochloride), ABAP, is the basis of theTotal Radical-Trapping Antioxidant Parameter, TRAP, method developed byWayner et al. (FEBS Lett. 1985;187(l):33-37). Upon addition of the ABAPto plasma, the length of time that oxygen uptake by peroxidizable plasmais inhibited is measured with an oxygen probe, and this value isreferred to as the TRAP. Trolox (a synthetic antioxidant used as astandard) is used in this method to induce a second reaction periodafter the natural antioxidants have been depleted. This second inductionperiod is used to calculate an R_(i) value, which is used to calculatethe TRAP value. The TRAP value is reported as the number of moles ofperoxyl radicals trapped per liter of fluid.

The duration of time is the only parameter measured in the TRAP methodand is a limiting factor in its analysis. The time taken to preventmaximum oxygen uptake cannot be measured easily and precisely, and thetotal radical trapping capability per mole of some antioxidants isdependent on their initial concentration. This analysis leaves out theextent of inhibition.

A modified TRAP assay was later published by Ghiselli et al. (FreeRadic. Biol. Med. 1995;18(1):29-36), which corrects for interferencesfrom plasma proteins or sample dilution. This modified method is basedon the ability of plasma to protect β-PE from peroxyl radical attackproduced by ABAP. Protection is accomplished by precipitating theprotein out of plasma with ammonium sulfate and ultracentrifugation. Themodified TRAP assay is performed by adding the reagents to quartzfluorometer cells and, after a 37° C. incubation for 5 minutes, ABAP isadded. Fluorescence is monitored at 495 nm every 5 minutes maintainingthe same temperature throughout the experiment.

This modified TRAP method produces a linear decrease in fluorescence dueto the thermal decomposition of ABAP. A period of total protection isindicated by a lag phase upon the addition of any antioxidant compound.It is assumed that the total plasma antioxidant capacity is directlyrelated to the length of the lag phase. The TRAP is quantified bycomparing the lag phase produced by the antioxidant compound to the lagphase produced by a Trolox solution of known concentration. The modifiedTRAP method does not measure the ability of plasma to break the lipidperoxidation chain triggered by ABAP, and it is not fully definedwhether and to what extent lipid-soluble antioxidants are involved inTRAP.

The present invention addresses these problems in the art and providesan assay that measures oxygen uptake of a complete system, allowing forselection of optimum ratios of ingredients for an antioxidantcomposition. An optimized synergistic antioxidant composition is alsoprovided.

SUMMARY OF THE INVENTION

The present invention is based, in part, on a new method of measuringantioxidant activity of a composition by measuring oxygen uptake of asystem and by dissolving a test composition in a detergent-containingsolvent at less than saturation conditions.

Further, the present invention provides an antioxidant compositionhaving synergistic antioxidant activity that, while not wanting to bebound by theory, is believed by the present inventors to have activityfor protecting intracellular cytosol, cellular membranes, andextracellular fluid such that the body is protected throughout byantioxidant activity.

An effective antioxidant supplement prevents the buildup of unpairedelectrons in an organelle or body fluid. Different antioxidantsconcentrate in different areas of a cell or organelle, depending onwhether the antioxidants are lipid- or water-soluble or synthesized in aspecific cellular compartment (e.g. glutathione in the cytosol). If moreof a particular category of antioxidants (i.e., fat-soluble,water-soluble) is available in a particular organelle or body fluid thanis needed to balance the available unpaired electrons, that antioxidantconcentrates in and serves as a “sink” for unpaired electrons, producingsuperoxide radicals, peroxide radicals, or hydroxyl radicals at a fasterrate, i.e. it actually becomes a pro-oxidant. For thisantioxidant-mediated process the present inventors coined the term“antioxidant capacitor effect.”

For example, vitamin E, a lipid-soluble vitamin, concentrates in thelipid membranes of cells. If more of this vitamin is available than isneeded to balance the unpaired electrons in the membrane, and/or thereis an insufficient amount of co-antioxidants available to regenerate thevitamin E, tocopherol-mediated peroxidation is believed to occur. Thatis, vitamin E is believed to concentrate in the lipid membranes andserves as a “sink” for unpaired electrons producing peroxide radicals inthe membrane at a faster rate. Thus, when taken in excessive,disproportional amounts, vitamin E actually becomes a pro-oxidant. Thisis the antioxidant capacitor effect. A similar effect can resultwhenever an imbalance occurs (whether in fat-soluble or water-solubleareas) that impedes elimination of free radicals from the body.

The present invention provides an antioxidant composition comprising aflavonoid selected from the group consisting of a flavone, a flavonol,an isoflavone, an isoflavonol, an analogue thereof, a pharmaceuticallyacceptable salt thereof, and a mixture thereof; and a mixture of atleast two forms of vitamin E selected from the group consisting ofalpha, beta, delta, epsilon, gamma, zeta, eta, xi1, xi2, and sigmatocopherols, and alpha, beta, delta and gamma tocotrienols, andderivatives thereof; wherein the ratio of flavonoid to mixture ofvitamin E forms is 40/60 to 90/10 precent by weight. The antioxidantcomposition may further comprise bush plum, green tea extract, grapeskin extract, or a mixture thereof.

The flavonoid and mixture of vitamin E forms are defined herein as“primary ingredients,” and the primary ingredients are present in theantioxidant compositions of the present invention in an amount of 12.1%up to 100% by weight, of 30% to 85% by weight, or, in anotherembodiment, 82% by weight.

The bush plum, green tea extract, grape skin extract, or a mixturethereof are defined herein as “secondary ingredients,” and the secondaryingredients are present in the antioxidant compositions of the presentinvention in an amount of greater than 0% to 87.9% by weight, of 15% to70% by weight, or, in another embodiment, 18% by weight. In anotherembodiment, the secondary ingredients include a combination of grapeskin extract and green tea extract present in the composition in aweight ratio of 60/40 to 80/20. In a further embodiment, the antioxidantcomposition further comprises bush plum in an amount of 2% by weight ofthe composition.

In one embodiment of the antioxidant composition, the flavonoid is aflavonol, and the flavonol is selected from the group consisting ofquercetin, kaempferol, myricetin, an analogue thereof, apharmaceutically acceptable salt thereof, and a mixture thereof. In afurther embodiment of the invention, the flavonol is quercetin.

In another embodiment of the invention, the vitamin E forms are selectedfrom the group consisting of alpha, beta, delta, and gamma tocopherol.

An embodiment of the invention is an antioxidant composition comprisingquercetin, a mixture of alpha, beta, delta, and gamma tocopherols, grapeskin extract, green tea extract, and bush plum wherein the quercetin andmixture of alpha, beta, delta, and gamma tocopherols comprise 12.1% upto 100% by weight of the composition, and wherein the quercetin andmixture of alpha, beta, delta, and gamma tocopherols are present in aweight percent ratio of 40/60 to 90/10. In one embodiment of theinvention, the quercetin, tocopherols, grape skin extract, green teaextract, and bush plum have weight ratios of 49/33/9.5/6.5/2. In such anembodiment, the antioxidant activity is at least 10,000 micromolesTrolox equivalent units per gram, using an ORAC(o) oxygen uptakemeasuring assay.

According to a further embodiment, the antioxidant composition of thepresent invention further comprises a carrier comprising gum acacia,xanthan gum, gum tragacanth, gum ghatti, and aloe vera gel extract,wherein the composition and carrier have a weight ratio of 1:2 to 2:1.The carrier components, namely, gum acacia, xanthan gum, gum tragacanth,gum ghatti, and aloe vera gel extract are present in the carrier in aweight ratio of 30/30/20/19/1. The antioxidant composition and carriercombination may be roller-compacted and, according to one embodiment, isroller compacted at a weight ratio of 1:2.

A method for measuring antioxidant activity of a test sample havingwater and lipid-soluble ingredients by measuring oxygen uptake is afurther embodiment of the present invention. The method comprisescombining an oxidizable target molecule and the test sample in a solventof acetone/water/detergent to form a test mixture at 37° C. underconditions where oxygen is present in equilibrium with air; adding anazo radical initiator to the test mixture; and measuring area under anoxygen uptake curve of the test mixture to provide a measure of theantioxidant activity of the test sample. This method may furthercomprise the steps of combining an oxidizable target molecule and asolvent of acetone/water/detergent to form a control mixture at 37° C.under conditions where oxygen is present in equilibrium with air;combining an oxidizable target molecule and Trolox in a solvent ofacetone/water/detergent to form a standard mixture at 37° C. underconditions where oxygen is present in equilibrium with air; adding anazo radical initiator to the control mixture and to the standardmixture; measuring area under an oxygen uptake curve of the controlmixture and the standard mixture; and determining antioxidant activityin Trolox equivalents to provide a measure of the antioxidant activityof the test sample. The test sample may comprise either water-solubleingredients or lipid-soluble ingredients, or both water-soluble andlipid-soluble ingredients.

A method of measuring stability of an antioxidant composition over time,the composition having water and lipid-soluble ingredients, by measuringoxygen uptake of the composition at a first time point and at a second,later, time point, is an embodiment of the present invention. The methodcomprises combining an oxidizable target molecule and the antioxidantcomposition in a solvent of acetone/water/detergent to form a testmixture at 37° C. under conditions where oxygen is present inequilibrium with air; adding an azo radical initiator to the testmixture; and measuring area under an oxygen uptake curve of the testmixture to provide a measure of the antioxidant activity of theantioxidant composition at the first time point and at the second timepoint, wherein a difference between the area under the oxygen uptakecurve for the first time point and the area under the oxygen uptakecurve for the second time point is a measure of stability of theantioxidant composition over time.

A further embodiment of the invention is a process of formulating anantioxidant composition having time release and increased shelf life.The process comprises blending the antioxidant composition of thepresent invention with a carrier comprising gum acacia, xanthan gum, gumtragacanth, gum ghatti, and aloe vera gel extract in a weight ratio of30/30/20/19/1; wherein the composition and carrier have a weight ratioof 1:2 to 2:1 to form a blend; roller compacting the blend to form acompact; milling the compact to form a granulation; and forming thegranulation into a dosage form.

A process of increasing the shelf life of an antioxidant formulation isan aspect of the present invention. The process comprises combining theantioxidant formulation and a carrier comprising gum acacia, xanthangum, gum tragacanth, gum ghatti, and aloe vera gel extract in a weightratio of 30/30/20/19/1; wherein the composition and carrier have aweight ratio of 1:2 to 2:1 to form a blend; and roller compacting theblend to form a compact.

A method of increasing serum antioxidant activity of an individualcomprising administering 500 mg to 1 g of the antioxidant composition ofthe present invention per day to the individual is a further aspect ofthe present invention. An increase of up to 36.5% in antioxidantactivity, as indicated by serum ORAC β-PE values, was observed bysupplementation of the diet of individuals using the compositionprovided herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an antioxidant effect of the combination of quercetin (Q)at 5 μg/mL and mixed tocopherols (MT) at 5 μg/mL as compared to eachingredient separately at a concentration of 10 μg/mL as measured by theORAC(o) method of the present invention.

FIG. 2 shows area under the curve (AUC) results for varying ratios ofquercetin and mixed tocopherols using the ORAC(o) method to measureantioxidant capacity. The total concentration of sample (Q+MT) is 10μg/mL for each percentage assayed. For example, at 0% quercetin, theconcentration of mixed tocopherols is 10 μg/mL, and there is noquercetin in the sample. At 10% quercetin, the sample has 1 μg/mL ofquercetin and 9 μg/mL of mixed tocopherols. At 20% quercetin, the samplehas 2 μg/mL of quercetin and 8 μg/mL of mixed tocopherols. The synergyis readily observed between 40 and 100% quercetin, and most readily from40 to 90% quercetin. The straight line represents the additive effect,i.e., at 10% quercetin, the line represents the sum of 90% of theactivity of mixed tocopherols alone and 10% of the activity of quercetinalone. A synergistic effect is found above this line.

FIG. 3 shows ORAC(o) assays for varying ratios of grape skin extract andgreen tea extract in the presence of 49.18% quercetin, 32.79% mixedtocopherols, and 1.64% bush plum. The optimal ratio of grape skinextract to green tea extract is 60/40 to 80/20.

FIG. 4 shows ORAC(fl) results of the combination of quercetin (Q) at 5μg/mL and mixed tocopherols (MT) at 5 μg/mL as compared to eachingredient separately at a concentration of 10 μg/mL.

FIG. 5 shows an HPLC chromatogram designed to examine flavonoidcomponents of the Australian bush plum (Terminalia ferdinandiana). Thechromatogram is from a reverse phase C₁₈ column using a stepped gradientof 0.1% trifluoroacetic acid and 100% methanol, at a flow rate of 1mL/min using a sample of methanol and water-extracted bush plum powder.The conditions were developed to separate out flavonoids and vitamin C.The absorbance was measured at 245 nm. A peak corresponding to vitamin Cis indicated, as well as a peak that is due to solvent.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a performance assay that measures theoxygen radical absorption capacity (ORAC) of a composition comprisinghydrophobic and/or hydrophilic antioxidants. The term ORAC(o) is usedsince the assay measures the ability of antioxidants to quench radicalsby directly tracking the disappearance of oxygen. Current industrystandard assays (ORAC(fl) and ORAC(β-PE)) measure antioxidant capacityby indirectly measuring degradation of a fluorescent compound(fluorescein or β-phycoerythrin) as marked by the disappearance offluorescence. These assays work well with hydrophilic antioxidants, buthave limited effectiveness in measuring hydrophobic antioxidants ormixtures of hydrophobic and hydrophilic antioxidants.

Since human cells require both hydrophobic and hydrophilic antioxidants,a method that directly and effectively measures the antioxidant activityof both in one assay as presented herein is desirable and an improvementover the presently used assays.

Antioxidants can act by scavenging reactive free radicals or otherreactive oxygen species such as O^(2•)—, H₂O₂, HOCl, ferryl, peroxyl,peroxynitrite, or alkoxyl, for example, or by preventing theirformation, or by converting the free radical or other reactive oxygenspecies to a less reactive species.

Components of the ORAC(o) assay for antioxidant activity of the presentinvention are as follows.

Radical Initiator: Azo radical initiators are present in the ORAC(o)assay of the present invention at a concentration such as to generateradicals for measurements of antioxidant activity. Azo initiatorsinclude, for example,2,2′-azobis[2-(5-methyl-2-imidazolin-2-yl)propane]dihydrochloride, 2,2′azobis (2-amidinopropane)dihydrochloride (AAPH),2,2′-azobis(2-amidinopropane)[2-(N-stearyl)amidinopropane]dihydrochloride (SA-1),2,2′-azo(2-(2-imidiazolin-2-yl)-propane)-[2-[2-(4-n-octyl)imidazolin-2-yl]-propane]dihydrochloride (C-8), 2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile)(MeO-AMVN), 2,2′-azobis(2,2′-azobis (2,4-dimethylvaleronitrile) (AMVN),azo-bis-isobutylnitrile, 2,2′-azobis (2-methylproprionate) (DAMP), and2,2′-azobis-(2-amidinopropane).

In one embodiment of the assay, the radical generator is 2,2′ azobis(2-amidinopropane) dihydrochloride (AAPH). Decomposition of AAPHproduces molecular nitrogen and two carbon radicals. The carbon radicalsmay combine to produce stable products or react with molecular oxygen togive peroxyl radicals. The half life of AAPH is about 175 hours (37° C.at neutral pH). Therefore, the rate of free radical generation isessentially constant during the first several hours in solution. AAPH isused effectively for lipid peroxidation in aqueous dispersions of fattyacids.

Target Molecules: Linoleic acid is the target oxidizable molecule forthe ORAC(o) assay. Further unsaturated fatty acids, includingpolyunsaturated fatty acids (PUFA's), having a carbon chain length of 6to 20 carbons may be substituted for linoleic acid. AAPH will oxidizelinoleic acid, as well as any other oxidizable compound in the systemincluding the antioxidant being tested. The assay measures the abilityof various antioxidants to protect against the AAPH-induced freeradicals.

Solvent System: While the solvent system for the initial extraction withthe prior art ORAC(fl) method involves putting 500 mg of sample in 20 mLof one-half acetone and one-half water (25 mg/mL), followed by dilutionswith buffer, the solvent system for the ORAC(o) involves dissolvingsamples in one-third acetone, one-third water, and one-third detergent(“one-third” solvent) at a concentration of 1 mg/ML. Dilutions are thenmade using the same solvent. The detergent may be a nonionic detergentsuch as TWEEN®, (i.e., TWEEN®20), BRIJ®, or TRITON®; a zwitterionicdetergent such as CHAPS®; a cationic detergent; or an anionic detergentsuch as cholate, deoxycholate, sodium dodecylsulfate, or TWEEN®-80; or asurfactant. The ratio of water to acetone to detergent may vary by up toabout 10%.

Applications of the ORAC(o) Assay of the Present Invention: The ORAC(o)assay may be used to measure the total antioxidant activity for serum,lipid-soluble serum fraction, water-soluble serum fraction, urine,lipid-soluble urine fraction, water-soluble urine fraction, LDLfraction, tissue homogenates, quality control of antioxidantsupplements, food products, or preservatives, development of newantioxidant supplements, development of new food products, newpreservatives, or new antioxidant therapies, quality control of foodmanufacturing and processing, assessing antioxidant activity of plants,or monitoring the antioxidant activity of cosmetic products, forexample.

The assay of the present invention is also provided for determining acondition under which an antioxidant may have activity of a pro-oxidant,i.e., the antioxidant is present under conditions where it promotesoxidation of a target rather than delaying or preventing oxidation of atarget molecule. A pro-oxidant has a negative ORAC(o) value.

Components of the Synergistic Antioxidant Composition of the PresentInvention: Using the performance antioxidant assay of the presentinvention, an antioxidant composition having synergistic activity isprovided that includes flavonoids such as quercetin, a mixture of atleast two forms of vitamin E, and optionally, grape skin extract, greentea extract and bush plum. The synergism is particularly observed in aweight ratio of quercetin to the mixture of vitamin E forms of 40/60 to90/10%. One embodiment of the composition includes the following weightratios: quercetin, 49.18%; mixed tocopherols, 32.79%; grape skinextract, 9.84%; green tea extract, 6.56%; and bush plum, 1.64%.

Flavonoids such as Quercetin: The flavonoid of the composition can be aflavone, a flavonol, an isoflavone, an isoflavonol, an analogue thereof,a pharmaceutically acceptable salt thereof, or a mixture thereof.Examples of a flavonol include quercetin, kaempferol, and myricetin. Theparticular flavonoid or flavonoid analogue or salt included in thecomposition is determined by running an ORAC(o) antioxidantdetermination. An activity within 80% percent of that of quercetin iscontemplated to provide an analogue. Reference to a flavonoid, inparticular, quercetin, also is intended to refer to the aglycone or aglycoside thereof where the sugar is arabinose, rhamnose, galactose orglucose, for example. The rhamnose glycoside of quercetin is known asrutin or quercetrin, and the rhamnose glycoside of myricetin is known asmyricitrin. Analogues of quercetin include those compounds whichcomprise a substituting group other than an —OH group at one or more ofthe positions 3, 5, 7, 3′, and 4′. Other substituting groups include:alkyl less than 5 carbon atoms, acetyl, sulphyl, or malonyl. Foranalogues of quercetin, only one or two of the positions are substitutedwith anything other than —OH groups.

A “pharmaceutically acceptable salt” is a salt of a flavonol with anorganic or inorganic acid generally accepted as safe for oralconsumption. Acid addition salts include chlorides, bromides, sulfates,nitrates, phosphates, sulfonates, formates, tartrates, maleates,malates, citrates, benzoates, salicylates, ascorbates, and others knownto those of ordinary skill in the art.

Flavonoids such as quercetin are readily synthesised in vitro. However,flavonoids (including quercetin) are present and are prepared fromnaturally occurring foodstuffs, in particular, fruits and vegetables,such as apples, pears, grapes, onions, red wine, bell peppers, redcurrants, black currants, lemons, cherries, cranberries, gooseberries,tomatoes, olives, radishes, kohlrabi, horseradish, potatoes, andasparagus. Quercetin can be obtained from Pharnline (Florida, N.Y.).

A Mixture of at least Two Forms of Vitamin E: By “a mixture of at leasttwo forms of vitamin E” is meant herein a mixture of at least two formsof tocopherol selected from alpha, beta, delta, epsilon, gamma, zeta,eta, xi1, xi2, and sigma tocopherols, and alpha, beta, delta and gammatocotrienols, and combinations or derivatives thereof. In oneembodiment, “a mixture of at least two forms of vitamin E” is a mixtureof at least two forms of tocopherol selected from alpha, beta, delta,and gamma tocopherol. In another embodiment, “a mixture of at least twoforms of vitamin E” is a mixture of alpha, beta, delta, and gammatocopherol. “A mixture of at least two forms of vitamin E” may beobtained from VITAECAPS, SA, Spain, from Henkel Corporation; or fromCognis Corporation (Kankakee, Il.), for example. COVITOL® F-350M iscommercially available from Cognis and contains natural sourcealpha-tocopherol with mixed tocopherols which are obtained from ediblevegetable oils. The particular mixture of tocopherols included in theantioxidant composition of the present invention is determined byrunning an ORAC(o) antioxidant determination. An activity within 80%percent of that of mixed tocopherols of the present invention iscontemplated to provide “a mixture of at least two forms of vitamin E.”

Salts or derivatives of tocopherols include pharmaceutically acceptablesalts such as acetate, sulfate, succinate, nicotinate, allophanate,phosphate, quinone, or halogenated derivatives; esters; stereoisomers;and the like. The invention encompasses the use of vitamin E derivativesin which substitutions, additions, and other alterations have been madein the 6-chromanol ring and/or side chain, with the proviso that thederivatives maintain antioxidant activity of a vitamin E. For example,tocopherols and their derivatives can vary by the number and position ofalkyl groups, double bonds and other substituents and variations on thering and side chain. An “alkyl” is a cyclic, branched or straight chainchemical group containing only carbon and hydrogen, such as methyl,butyl, and octyl. Alkyl groups can be either unsubstituted orsubstituted with one or more substituents, e.g., halogen, alkoxy,acyloxy, amino, hydroxyl, mercapto, carboxy, or benzyl. Alkyl groups canbe saturated or unsaturated at one or several positions. Typically alkylgroups will comprise 1 to 8 carbons, 1 to 6, or 1 to 4 carbon atoms.Additional tocopherols can be constructed by conjugation to the ringstructure or side chain of various other moieties, such as thosecontaining oxygen, nitrogen, sulfur and/or phosphorus. Tocopherolderivatives can also be made by modifying the length of the side chainfrom that found in prototypical tocopherols such as alpha-, beta-,delta- and gamma-tocopherol. Tocopherols can also vary instereochemistry and saturation of bonds in the ring structure and sidechain.

Additional tocopherol derivatives, including prodrugs, can be made byconjugation of sugars or other moieties to the side chain or ringstructure. Mixed tocopherols include without limitation mixtures ofstereoisomers of a single tocopherol (e.g., + and − stereoisomers ofalpha-tocopherol; (+/−) indicates a racemic mixture) or mixtures ofstructurally distinct tocopherols (e.g., alpha-plus gamma-tocopherol).

Bush Plum: The Australian bush plum (Terminalia ferdinandiana) containsabout 5% vitamin C and a variety of ingredients as demonstrated by anHPLC chromatogram at FIG. 5. These ingredients are believed to includeflavones, and flavonoids. The HPLC chromatogram is from a reverse phaseC₁₈ column using a stepped gradient of 0.1% trifluoroacetic acid and100% methanol, at a flow rate of 1 mL/min using a sample of methanol andwater-extracted bush plum powder. The conditions were developed toseparate flavonoids and to separate vitamin C. The absorbance wasmeasured at 245 nm.

Pulp and skin of a bush plum are removed from the seed of the fruit andmade into a slurry in water. The slurry is freeze-dried and ground. Forantioxidant compositions herein, the freeze-dried material is weighed inthe desired amount. Bush plum is present in the composition of thepresent invention in an amount of from 0% to 87.9%, or in anotherembodiment, about 2% by weight.

Grape skin extract: Grape skin extract is made from grape skins, andcontains 30-82% polyphenols and may be obtained from Polyphenolics,Madera, Calif.; Hunan Kinglong, Bio-Resource Co. Ltd, Changsha EconomicDevelopment Zone, China; or from Pharmline, Florida, N.Y.

Green tea extract: Green tea extract is an extract from the leaves ofCamellia sinensis, contains 35-95% polyphenols, and may be obtained fromAmax NutraSource Inc., Eugene, Oreg.; Blue California, Rancho SantaMargarita, Calif.; or from PL Thomas & Co., Morristown, N.J.

Other Ingredients: Antioxidant compositions of the present invention maycomprise a non-toxic, pharmaceutically acceptable carrier such aslactose, starch, sucrose, glucose, methyl cellulose, magnesium stearate,dicalcium phosphate, calcium sulfate, mannitol, sorbitol, cyclodextrin,cyclodextrin derivatives, or the like. Capsule or tablets can be easilyformulated and can be made easy to swallow or chew. Tablets may containsuitable carriers, binders, lubricants, diluents, disintegrating agents,coloring agents, flavoring agents, flow-inducing agents, or meltingagents. A tablet may be made by compression or molding, optionally withone or more additional ingredients. Compressed tablets may be preparedby compressing the active ingredient in a free flowing form (e.g.,powder, granules) optionally mixed with a binder (e.g., gelatin,hydroxypropylmethylcellulose), lubricant, inert diluent, preservative,disintegrant (e.g., sodium starch glycolate, cross-linked carboxymethylcellulose) surface-active or dispersing agent. Suitable binders includestarch, gelatin, natural sugars such as glucose or beta-lactose, cornsweeteners, natural and synthetic gums such as acacia, tragacanth, orsodium alginate, carboxymethylcellulose, polyethylene glycol, waxes, orthe like. Lubricants used in these dosage forms include sodium oleate,sodium stearate, magnesium stearate, sodium benzoate, sodium acetate,sodium chloride, or the like. Disintegrators include, for example,starch, methyl cellulose, agar, bentonite, xanthan gum, or the like.Molded tablets may be made by molding in a suitable machine a mixture ofthe powdered active ingredient moistened with an inert liquid diluent.

Capsules or tablets may optionally be coated or scored and may beformulated so as to provide slow- or controlled-release of theantioxidant composition. Timed-release compositions for controlledrelease of agents generally contain agent particles mixed with or coatedwith a material that is resistant to enteric degradation ordisintegration for a selected period of time. Release of the agent mayoccur by leeching, erosion, rupture, diffusion or similar actions.

Carriers may promote antioxidant stability as well as providing timerelease. A mixture of plant carbohydrates termed AMBROTOSE® PhytoFormula may be combined with the antioxidant composition. Such acombination extends the shelf life of the antioxidant composition andprovides for a time release form. AMBROTOSE® Phyto Formula contains, ina weight/weight ratio of about 30/30/20/19/1, gum Arabic(acacia),xanthan gum, gum tragacanth, gum ghatti, (which may be obtained fromTicGum) and aloe vera gel extract (inner leaf gel, Carrington Labs,Irving, Tex., Manapol® powder). The AMBROTOSE® Phyto Formula is blendedwith the antioxidant composition of the present invention in a weightratio of 2:1 to 1:2. In another embodiment, AMBROTOSE® Phyto Formula isblended with the antioxidant composition in a weight ratio of 2:1.

Capsules or tablets may contain further plant components in trace weightpercentages less than 0.1%, the components having no essentialsignificance to the composition.

Formulation Processes: A process of formulating a roller compactedantioxidant composition comprises blending AMBROTOSE® Phyto Formula withthe antioxidant composition set forth herein. The resultant blend istransferred to a roller compactor and compacted between rollers to forma compact. The pressure imparted on the blend enhances the physicaladhesion between the ingredients. The compact is subsequently milled toform a granulation. The resultant granulation is then formed into thedesired dosage form, such as capsules or tablets. A FitzpatrickChilsonator Model 4LX10D roller compactor was used herein, having rollsthat are notched across the face and perpendicular to the rotation,having a fixed force of 10 ton, and a Fitzmill screen of 0.093. Theroller compaction device may have variable rotation speed, forceapplication, and gap width capabilities, for example, a Gerteis Polygrandry roller compactor system (Gerteis, Germany). The roller compactorfunctions by uniformly applying pressure on a blend by passing the blendbetween two counter-rotating rollers. The pressure imparted on the blendby the rollers compresses the blend into a compact, such as a sheet orribbon, which is typically milled to produce granules. Alternatively,granulation may be achieved by slugging, milling or sieving as may berequired. Granules having a mesh of #20-80 are desired.

A longer shelf life of the roller compacted combination of theantioxidant composition with AMBROTOSE® Phyto Formula is believed due tothe reduction in the amount of surface area of the antioxidantcomposition exposed to oxygen. The roller compacted combination alsoeliminates the need for excipient fillers in the capsule ortablet-making process. Additional benefits of a combination ofAMBROTOSE® Phyto Formula with the antioxidant composition set forthherein include: provision of non-soluble fiber which may serve as a sinkfor unpaired electrons in the gut, and provision of monosaccharides forcorrect structure of cellular glycoforms responsible for cell-mediatedcommunication in repair of cells damaged by free radicals.

Dosage: Useful dosage formulations for administration of thecompositions of the present invention include capsules or tablets of100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000 mg of antioxidantcomposition. In one embodiment, no fillers, carriers, or stabilizers areadded to the composition. In another embodiment, AMBROTOSE® PhytoFormula is blended with the antioxidant composition of the presentinvention in a weight ratio of 2:1, 1:1, or 1:2. In another embodiment,AMBROTOSE® Phyto Formula is blended with the antioxidant composition ina weight ratio of 2:1. In another embodiment, a capsule or tabletprovides 500 mg of antioxidant composition blended with AMBROTOSE® PhytoFormula. For this embodiment, two tablets or capsules may be taken perday. Appropriate coatings may be applied to increase palatability ordelay absorption.

EXAMPLE 1 Comparison of Antioxidant Activity Using ORAC(fl) and ORAC(o)Assays

Ingredients for an antioxidant composition were analyzed for antioxidantactivity using a prior art oxygen radical absorption capacity methodthat measures flouresence (ORAC(fl)), and using the method of thepresent invention that measures dissolved oxygen (ORAC(o)). Theantioxidant activity of a product is its ability to protect the systemfrom damage caused by peroxyl radicals.

Prior Art Method of Measuring Antioxidant Activity for Comparison: Forthe ORAC(fl) assay, the method of Ou et al. (Ou, B., Hampsch-Woodill, M.and Prior, R. L., J. Agric. Food Chem. 2001, 49, 4619-4626) wasfollowed. Differences from the Ou procedure as published included thespeed of the orbital shaker (Ou, 400 rpm; herein, 280 rpm), and thecentrifuge speed (Ou, 14,000 rpm, 15 min; herein, 3200 rpm, 15 min andthe length of the assay (Ou, 30 min; herein, 100 min). Fluorescein,sodium salt, was obtained from Aldrich (Milwaukee, Wis.). For the Oumethod, a standard amount of fluorescein is added to an antioxidantproduct being tested, and the beginning level of fluorescence ismeasured. A free radical initiator is added, and the time and degree ofdisappearance of fluorescence are measured. Trolox, a syntheticantioxidant with a structure similar to vitamin E (i.e. a structuresimilar to a strong antioxidant which is consistent from lot-to-lot), isused as the standard and run for comparison with each sample. A blank(control) is also included in each run. Fluorescence vs. time isplotted. The blank (control) is subtracted from every curve. The netarea under the curve of the antioxidant is compared to the net areaunder the curve of Trolox. The larger the net area under the curve, thebetter the antioxidant. All ORAC(fl) analyses were performed on a COBASFARA II centrifugal analyzer (Roche Diagnostic System Inc., Branchburg,N.J.; excitation wavelength=493 nm and emission filter=515 nm). Resultsare given as micromoles of Trolox equivalents per gram of sample.

Method of Measuring Antioxidant Activity of the Present Invention: Forthe ORAC(o) assay of the present invention, the antioxidant productbeing tested is added to a solution containing a target molecule(linoleic acid) with oxygen present at equilibrium with the air. Then afree radical initiator is added, and the time it takes the oxygen todisappear is measured, yielding the rate of disappearance. Trolox isused as the standard, and a blank is run as a control. Amount ofdissolved oxygen vs. time is plotted allowing direct comparison of netareas under the curve. A detailed method is as follows:

Buffers (K₂HPO₄(F. W. 174.2), NaH₂PO₄(F W 120.0)) were obtained fromSigma (St. Louis, Mo.). Linoleic acid 99%, Trolox(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) 97%, TWEEN® 20,and 2,2′-azobis (2-methylpropionamidine) dihydrochloride 97% (AAPH),were obtained from Aldrich (Milwaukee, Wis.). HPLC grade acetone wasobtained from Fisher (Hampton, N.H.). A YSI 5300A biological oxygenmeter was obtained from YSI (Yellow Springs, Ohio) and used according tothe manufacturer's specifications.

Samples were prepared at a concentration of 1 mg/mL in “one-third”solvent. “One-third” solvent is equal parts of water, acetone, and asolution of TWEEN®20 diluted 1:9 with water. Samples were shaken for 1hour at room temperature on an orbital shaker at 280 rpm. The samplesolution was ready for analysis after further dilution (generally to 10μg/mL) with “one-third” solvent. “One-third” solvent was also used asthe blank.

The ORAC(o) assay was carried out using the YSI 5300A biological oxygenmeter. Linoleic acid was prepared by adding 0.18 mL of 75 mM phosphatebuffer (pH 7.4), 0.18 mL of 10 weight percent TWEEN®20 stock solution,and 0.44 mL of deionized water to 70.8 mg linoleic acid. AAPH wasprepared by adding 0.9 mL of buffer to 67.8 mg of AAPH. In the finalreaction volume (5.218 mL), linoleic acid (21.59 mM) was used as thetarget of free radical attack, and AAPH (19.00 mM) was used as a peroxylradical generator. Trolox (at 10 μg/mL) was used as a standard. Readingswere taken every second until a zero reading was observed.

The formula for calculating the ORAC(o) value (Oxygen Radical AbsorbanceCapacity oxygen specific electrode) is:

${{ORAC}(o)} = \frac{\frac{{AUC}_{SMP} - {AUC}_{BLNK}}{{AUC}_{TRLX} - {AUC}_{BLNK}} \times 1000 \times \lbrack {{TRLX}\mspace{14mu}( {{µmol}\text{/}{ml}} )} \rbrack}{\lbrack {{SMP}\mspace{14mu}( {{mg}\text{/}{ml}} )} \rbrack}$This calculation yields a quantity known as micromoles of Troloxequivalents per gram of sample. As used herein the terms “relativeORAC(o)” and “ORAC(o)” refer to the same value. A negative valuereflects less radical quenching activity than obtained with a blankwhich indicates that a composition is a pro-oxidant, i.e., an agent thatpromotes oxidation, rather than acting as an antioxidant.

Comparison of ORAC(o) and ORAC(fl) Assay Parameters:

A comparison of the assay parameters of the ORAC(fl) and the ORAC(o)methods is provided in Table 1.

TABLE 1 Assay Parameter During Assay ORAC(fl) ORAC(o) Temperature 37° C.37° C. AAPH concentration 1.28 × 10⁻² M in phosphate 19.00 mM inphosphate buffer buffer Target molecule concentration fluorescein, 43.8nM in 21.59 mM linoleic acid, in phosphate buffer mixture of 10% TWEEN ®20, buffer and water (.18 mL, .18 mL, .44 mL) Sample concentrationinitially at 500 mg in 20 mL, 1 mg/mL initially, diluted to supernatantsdiluted to 10 μg/mL 10 μg/mL with buffer Sample solvent acetone/water,50/50 v/v water/acetone/10% by weight dilutions in phosphate bufferTWEEN ® 20, v/v/v (“one-third” solvent) dilutions in “one-third” solventBuffer for assay, concentration 75 mM phosphate, pH 7.4 75 mM phosphate,pH 7.4 Final assay volume 400 μl 5.218 mL Blank (control) buffer“one-third” solvent Standard 62.5 μM Trolox in buffer Trolox at 10 μg/mL(38.755 μM) in “one-third” solvent Method of measuring antioxidantfluorescein yields a decrease in oxygen is taken up by the radicalcapacity of the sample fluorescence as it is oxidized by initiator, andby linoleic acid radicals, antioxidant protects carbon radicals;antioxidant and delays decrease protects and decreases oxygen uptake

Advantages of the ORAC(o) as Compared to the ORAC(fl):

Direct vs. Indirect Measurement of Antioxidant Potential: The ORAC(fl)is an indirect method in that it relies on the assumption that thefluorescein (target molecule) is the only fluorescent component beingmeasured. However, many antioxidant compounds fluoresce naturally (e.g.blueberries); and combinations of these compounds from radical-radicalreactions fluoresce also. Fluorescence from the sample, therefore, canskew the results of an assay based on fluorescence. The ORAC(o) method,on the other hand, is a direct measurement of oxygen uptake, a directmeasurement of the disappearance of oxygen into free radicals. Thismethod of measurement of antioxidant capacity is not dependent uponwhether the oxygen is attched to water- or lipid-soluble components.

Saturation of Samples: Ou et al. prepared samples in acetone/water(50:50, v/v) at a concentration of 500 mg in 20 mL, rotated them on arotary shaker at 400 rpm for 1 hour, centrifuged them at 14,000 rpm for15 minutes, and diluted them with 75 mM potassium phosphate buffer at pH7.4. The present inventors found that much of a test sample would not gointo solution under the Ou conditions (ORAC(fl) conditions), the moresoluble components displace the less soluble components. Consequently,only that which was solubilized under the ORAC (fl) conditions is whatmade up an ORAC(fl) sample, and a supernatant solution made according tothe ORAC(fl) method for analysis may not be representative of the actualsample. Since a solution of a sample in the ORAC(fl) buffer does notalways reflect the contents of the sample, results can be skewed usingthe ORAC(fl).

The problem with sample dissolution was recognized and a lack ofcontribution of mixed tocopherols to an antioxidant measurement carriedout on a mixture of quercetin and mixed tocopherols when using theORAC(fl) was observed. FIG. 1 shows that the ORAC(o) demonstrates anantioxidant effect of the combination of quercetin at 5 μg/mL and mixedtocopherols at 5 μg/mL as compared to each ingredient separately at 10μg/mL. In contrast, FIG. 4 shows that the ORAC(fl) shows no furthereffect from the same combination beyond the value for quercetin alone.Lack of activity from such a combination with mixed tocopherols andsaturation problems are absent from the ORAC(o) method since theconcentration of sample is more dilute and since the solvent for thesample contains acetone, water, and a detergent for solubilizing allcomponents of a sample. Presence of TWEEN®20 in the solvent for thesample accounted for detection of activity from mixed tocopherols.

Automation: The ORAC(fl) method is automated (Cobas Fara II by RocheDiagnostic Systems), which provides the ability to run numerous samplesat once and minimizes potential for human error. The ORAC(fl) method canalso be performed using a fluorometer without automation. Since theORAC(o) method is not yet automated, it is more labor intensive at thepresent time, however, the ORAC(o) method is expected to be automated.

Expense: A new, automated machine capable of running the ORAC(fl) cancost $250,000; a non-automated fluorometer costs about $50,000; theORAC(o) method, which uses an oxygen-specific electrode, can be set upfor only several hundred dollars.

Precision of Results: In the present assays, the fluorometer appeared toprovide more precise results than the oxygen probe, possibly because itis automated.

Validation: Validation, as conducted by the Association of OfficialAnalytical Chemists (AOAC) guidelines for single laboratory validationprovided results in Tables 2, 3, and 4.

TABLE 2 5 Day Trial for Precision (Repeatability) Area under Curve Day 1202.655447939563 Day 2 212.901122995373 Day 3 187.01466464995 Day 4202.856617129109 Day 5 (2^(nd) Analyst) 213.124092629655 5 Day Mean203.710389068730 Standard Deviation 10.649840914564 Relative StandardDeviation 5.23% HORRAT 1.981060606061The values for each day are an average of 3 runs of the quercetin sampleat a concentration of 10 μg/mL. The HORRAT value is the ratio betweenobserved RSD_(R) values and the RSD_(R) values predicted by the Horwitzequation known to those of skill in the art, and is regarded as anindication of the acceptability of a method with respect to itsprecision. In a single laboratory performance study, a series of HORRATratios between 0.5 and 2.0 indicate acceptable precision of a method.The HORRAT value for the 5-day trial is 1.98.

A determination of the analytical range as a linear range is provided inTable 3.

TABLE 3 Determination of Analytical Range Sample (μg/ml) Area UnderCurve   1 124.567114093960  10 209.388111888112  100 693.611111111111 500 2327.96518987343 1000 2870.09540636041

-   y=2.8335x+332.16; R²=0.9231 for 1-1000 plot-   y=4.3353x+176.66; R²=0.9967 for 0-500 plot

Linear integrity appears to decline as the sample concentration nears1000 μg/mL. With the determination of the analytical range as a linearrange, the value of the area under the curve of variable concentrationsup to 500 μg/mL is determined.

Table 4 provides results for precision of single-day results.

TABLE 4 Single Day Trial for Precision (Repeatability) Area under curveRun 1 207.369402985075 Run 2 198.18118466899 Run 3 205.035211267606 Run4 201.586572438162 Run 5 202.110714285714 5 Run Mean 202.856617129109Standard Deviation 3.505016471434 Relative Standard Deviation 1.73%HORRAT 0.654480870834The single day precision trial involved 5 separate runs of the quercetinsample at a concentration of 10 μg/mL. The HORRAT value of Table 4 forthe ORAC (o) method is 0.65448.

Accuracy: The ORAC(o) is believed by the present inventors to be moreaccurate than the ORAC(fl) for the reasons stated herein.

Results: The ORAC(o) assay was used to optimize ratios of theingredients in an antioxidant composition as set forth in Example 2. Oneembodiment of the composition having weight ratios of quercetin, 49.18%;mixed tocopherols, 32.79%; grape skin extract, 9.84%; green tea extract,6.56%; and bush plum, 1.64% gave an antioxidant value using the ORAC(o)of 17,254 micromoles Trolox equivalents per gram. The same compositiongave an antioxidant value using the ORAC(fl) of 5,281 micromoles Troloxequivalents per gram. These data demonstrate that the ORAC(o) andORAC(fl) methods of measuring antioxidant activity differ in the resultsobtained. The inventors of the present invention believe that theORAC(o) method is preferred for the reasons stated supra.

EXAMPLE 2 A Synergistic Antioxidant Composition

According to the present invention five ingredients were combined intoan antioxidant composition, each of which is prominent in the diet oflong-lived peoples from regions around the world. Flavonols, mixedtocopherols, grape skin extract, green tea extract, or bush plum areprominent in the diet of peoples of the Andean village of Vilcabamba inEcuador, the land of Huza in the Karakoram Range in Kashmir, or inAbkhazia in the Georgian State of the former USSR, for example, as citedin Leaf A., Launois J. “A Scientist Visits Some of the World's OldestPeople,” National Geographic. 1973 January; of the Italian island ofSardinia (Koenig R. “Sardinia's Mysterious Male Methuselahs,” Science.2001, Mar. 16), and of Australia.

The present invention has demonstrated a synergistic antioxidantactivity of the compositions of the present invention. Not wanting to bebound by theory, the present inventors believe the various ingredientsof the antioxidant composition have activity for protectingintracellular cytosol, cellular membranes, and extracellular fluid suchthat the body is protected throughout. The bush plum component is high,for example, in natural vitamin C content, which can get into the cell,is hydrophilic, and is available for protecting the cytosol; the grapeskin extract and green tea extract are hydrophilic, cannot enter thecell and are available for protecting extracellular fluid; and mixedtocopherols are lipophilic, and together with flavonols (e.g.,quercetin), which are both hydrophilic and lipophilic, protectmembranes.

FIG. 2 shows area under the curve (AUC) results for varying ratios ofquercetin and mixed tocopherols using the ORAC(o) method to measureantioxidant capacity. The total concentration of sample (Q+MT) is 10μg/mL for each percentage assayed. For example, at 0% quercetin, theconcentration of mixed tocopherols is 10 μg/mL, and there is noquercetin in the sample. At 10% quercetin, the sample has 1 μg/mL ofquercetin and 9 μg/mL of mixed tocopherols. At 20% quercetin, the samplehas 2 μg/mL of quercetin and 8 μg/mL of mixed tocopherols. The synergyis readily observed between 40 and 100% quercetin, and most readilyobserved from 40 to 90% quercetin. The straight line represents theadditive effect, i.e., at 10% quercetin, the line represents the sum of90% of the activity of mixed tocopherols alone and 10% of the activityof quercetin alone. A synergistic effect is found above this line.

The primary ingredients of the composition of the present invention(flavonoids, as represented by quercetin, and a mixture of at least twoforms of vitamin E) comprise from 12.1% to 100%, 30% to 85%, or inanother embodiment, about 82% by weight of the five ingredients. In oneembodiment, the amount of quercetin is 49.18% and the amount of vitaminE forms is 32.79% of the total weight of the five ingredients.

The secondary ingredients of the composition of the present invention(grape skin extract, green tea extract, and bush plum) comprise from 0%to 87.9%, 15% to 70%, or about 18% by weight of the five ingredients.The optimal ratio of grape skin extract and green tea extract wasdetermined in the presence of 49.18% quercetin, 32.79% mixedtocopherols, and 1.64% bush plum as shown in FIG. 3. The optimal ratioof grape skin extract to green tea extract is 60/40 to 80/20. In oneembodiment, the grape skin extract is 9.84% and the green tea extract is6.56% of the total weight of the antioxidant composition.

Bush plum (Terminalia ferdinandiana) is provided as an ingredient of thecomposition in an amount from 0% to 87.9%, or in another embodiment, 2%.In the embodiment of FIG. 3, the bush plum is 1.64% of the composition.

The ORAC(o) assay shows that an antioxidant blend having the followingweight ratios: quercetin, 49.18%; mixed tocopherols, 32.79%; grape skinextract, 9.84%; green tea extract, 6.56%; and bush plum, 1.64% has anantioxidant activity of 17,254 micromoles Trolox equivalents per gram.

EXAMPLE 3 Stability of AMBROTOSE AO™

At this writing, AMBROTOSE AO™, a blend of AMBROTOSE® and theantioxidant formulation of the present invention at a 2:1 weight ratio,has been shown to maintain its activity under accelerated stabilityconditions (40° C. at 75% relative humidity) equating to a shelf-life ofroughly six months.

EXAMPLE 4 Antioxidant Effect of AMBROTOSE AO™ in Healthy Individuals

The present study was designed to determine the in vivo antioxidantactivity of different amounts of Ambrotose AO™ as determined by serumORAC(β-PE) and urine lipid hydroperoxide analyses. Thirteen healthy maleand female adult volunteers taking no nutritional supplements or anydrug that would interfere with the study were enrolled. Twelvevolunteers, ages 22-61, including 4 males and 8 females, consumedincreasing amounts of the antioxidant supplement. Of those, six usedtobacco products. Serum ORAC(β-PE) values, indicators of oxidativeprotection, and urine lipid hydroperoxide levels, markers of oxidativedamage, were chosen to assess subjects oxidative stress states. Duringthe study participants continued their normal pre-study daily routines.

Subjects had morning fasting serum ORAC(β-PE) and urine lipidhydroperoxide analyses performed after an initial washout period of 2weeks (on no supplements) and at the end of 2 weeks on each of theamounts of the AMBROTOSE AO™. The amounts used were 500 mg (1 capsule)each day for the first 14 days of supplement use, 1 g (2 capsules) eachday for the second 14-day period, and 1.5 g (3 capsules) each day duringthe third 14-day period. Serum samples were collected by a phlebotomistfrom Cover-Tek, Inc., an independent company in Dallas, Tex., and serumand urine samples were immediately packed in dry ice and shippedovernight for analysis by Genox Corporation, an independent laboratoryin Baltimore, Md. All samples were stored in dry ice at Genox, andanalyses were done at the same time at the conclusion of the study tominimize any analytical variability. Statistical analyses were performedby Decision Analyst, Inc., an independent firm in Arlington, Tex.

The precision of the analyses was tested by sending in a blinded controlsample in triplicate. ORAC(β-PE) values varied ±4.4%, staying wellwithin the expected limits of the assay, and thehydroperoxide/creatinine values varied ±1.5%.

Average ORAC(β-PE) in micromoles Trolox equivalents per gram at the endof each period for the twelve participants is as follows:

end of washout period 4280 two weeks on 500 mg 4898 further two weeks on1 g 5841 further two weeks on 1.5 g  4815.A paired t-test was conducted to determine if there was a differencebetween the ORAC baseline data and the ORAC period 1 data. The baselinemean (4279.49) was significantly lower than the period 1 mean (4898.31)at approximately 90% confidence (p=0.094). A paired t-test also wasconducted to test for a difference between the ORAC baseline and theORAC period 2 data. The baseline mean (4279.49) was significantly lowerthan the period 2 mean (5841.08) at approximately a 99% confidence level(p=0.000).

Lipid hydroperoxide values in micromolar/(mg/dl) are corrected for urineconcentration variability by dividing by urine creatinine as measured atthe same time on the same sample and are as follows:

end of washout period .0920 two weeks on 500 mg .0808 further two weekson 1 g .0782 further two weeks on 1.5 g .0764A paired t-test was conducted to determine if there was a differencebetween the Lipid Hydroperoxide Creatinine baseline data and the LipidHydroperoxide Creatinine period 1 data. The baseline mean (0.0908) wasnot significantly higher than the period 1 mean (0.0817) (p=0.511). Apaired t-test also was conducted to test for a difference between theLipid Hydroperoxide Creatinine baseline and the Lipid HydroperoxideCreatinine period 2 data. The baseline mean (0.0908) was notsignificantly higher than the period 2 mean (0.0775) (p=0.613).

Air quality is known to affect levels of oxidative stress. The poorerthe air quality, the greater the oxidative stress. A summary of theaverage US Environmental Protection Agency (EPA) air quality index foreach two-week period in the Dallas/Fort Worth area, which is where thesubjects lived, is as follows (a value of 1.0 describes good airquality, a value of 2.0 describes moderate air quality, and a value of3.0 is considered unhealthy for sensitive groups):

end of washout period 1.0 two weeks on 500 mg 1.0 further two weeks on 1g 1.4 further two weeks on 1.5 g  1.8.

Increased consumption of fruits and vegetables from the usual five to anexperimental ten servings a day was found in a clinical study tosignificantly increase serum ORAC(β-PE) values by approximately 13%after two weeks (Cao et al., Am. J Clin. Nutr. 1998:68, 1081-1087). Inthe present study, the increase in average serum ORAC(β-PE) values usingeach amount of supplement were, 14.4% with 500 mg, 36.5% with 1.0 g, and12.5% with 1.5 g. These data suggest that the optimum amount thatresults in the greatest rise in serum ORAC(β-PE) over baseline is 1.0 g.The percentage increase with 1.0 g is greater than the published 10%found by adding five fruits and vegetables to the diet.

The urine hydroperoxide/creatinine values decreased with increasingsupplement use. Percentage decrease with each amount was 12.1% with 500mg, 15.0% with 1.0 g, and 17.0% with 1.5 g suggesting that protectionfrom lipid damage increased with increasing amounts of supplement overthe range used.

The hydroperoxide data do not correlate exactly with the ORAC(β-PE)values in suggesting that 1.0 g is the optimal amount to use. SerumORAC(β-PE) is a measure of the antioxidant protection of the blood inregard to its ability to quench free radicals at the time of themeasurement. Urine lipid hydroperoxides are a marker of lipid oxidativedamage at some time in the past. The temporal relationship between theactual lipid damage, and the appearance of hydroperoxides in the urineis not well-defined. It may well be that these temporal differencesaccount, in part, for this variance.

Participants in the study lived in the Dallas/Ft Worth (DFW) area. Thepublished EPA daily air quality assessments for DFW were averaged foreach two week period. Air quality was, on average, getting worse overthe course of the study. This would normally be expected to decreaseoxidative protection, and hence ORAC(β-PE), and increase oxidativedamage and urine lipid hydroperoxides. Yet, increased protection anddecreased damage were evident, suggesting that the protection affordedby the supplement could have been greater than actually measured.

These data demonstrate that the present antioxidant supplement increasesantioxidant protection in consumers as measured by serum ORAC(β-PE) anddecreases lipid oxidative damage as measured by urine lipidhydroperoxides.

Those of skill in the art, in light of the present disclosure,appreciate that obvious modifications of the embodiments disclosedherein can be made without departing from the spirit and scope of theinvention. All of the embodiments disclosed herein can be made andexecuted without undue experimentation in light of the presentdisclosure. The full scope of the invention is set out in the disclosureand equivalent embodiments thereof. The specification should not beconstrued to unduly narrow the full scope of protection to which thepresent invention is entitled.

As used herein and unless otherwise indicated, the terms “a” and “an”are taken to mean “one”, “at least one” or “one or more”.

1. An antioxidant composition comprising: a flavonoid selected from thegroup consisting of a flavone, a flavonol, an isoflavone, anisoflavonol, an analogue thereof, a pharmaceutically acceptable saltthereof, and mixtures thereof; and a mixture of at least two forms ofvitamin E selected from the group consisting of alpha, beta, delta,epsilon, gamma, zeta, eta, xi1, xi2, and sigma tocopherols, and alpha,beta, delta and gamma tocotrienols, and derivatives thereof; bush plumpulp and skin comprising 5% vitamin C; green tea extract comprising35-95% polyphenols; and grape skin extract comprising 30-82%polyphenols; wherein the flavonoid and mixture of vitamin E forms areprimary ingredients and the primary ingredients are present in thecomposition in an amount of from 30% to 85% by weight and act in synergyto provide a higher antioxidant capacity; wherein the bush plum pulp andskin, the green tea extract, and the grape skin extract are secondaryingredients and the secondary ingredients are present in the compositionin an amount of from 15% to 70% by weight; wherein the flavonoid and themixture of vitamin E forms are present in the composition in a weightratio of from 40/60 to 90/10 percent; and wherein the grape skin extractand the green tea extract are present in the composition in a weightratio of from 60/40 to 80/20 percent.
 2. The antioxidant composition ofclaim 1 wherein the primary ingredients are present in the compositionin an amount of 82% by weight.
 3. The antioxidant composition of claim 1wherein the secondary ingredients are present in the composition in anamount of 18% by weight.
 4. The antioxidant composition of claim 1wherein the bush plum pulp and skin is present in the composition in anamount of 2% by weight.
 5. The antioxidant composition of claim 1wherein the flavonoid is a flavonol and the flavonol is selected fromthe group consisting of quercetin, kaempferol, myricetin, analoguesthereof, pharmaceutically acceptable salts thereof, and mixturesthereof.
 6. The antioxidant composition of claim 5 wherein the flavonolis quercetin.
 7. The antioxidant composition of claim 1 wherein thevitamin E forms are selected from the group consisting of alpha, beta,delta, and gamma tocopherol.
 8. An antioxidant composition comprisingquercetin, a mixture of alpha, beta, delta, and gamma tocopherols, grapeskin extract comprising 30-82% polyphenols, green tea extract comprising35-95% polyphenols, and bush plum pulp and skin comprising 5% vitamin C,wherein the quercetin and the mixture of tocopherols are present in thecomposition in an amount of from 30% to 85% by weight and in a weightratio of from 40/60 to 90/10 percent and wherein the grape skin extractand the green tea extract are present in the composition in a weightratio of from 60/40 to 80/20 percent and act in synergy to provide ahigher antioxidant capacity.
 9. The antioxidant composition of claim 8wherein the weight ratios of the quercetin, the mixture of tocopherols,the grape skin extract, the green tea extract, and the bush plum pulpand skin are 49/33/9.5/6.5/2 percent, respectively.
 10. The antioxidantcomposition of claim 8 wherein the composition has an antioxidantactivity of at least 10,000 micromoles Trolox equivalent units per gram,using an ORAC(o) oxygen uptake measuring assay.
 11. The antioxidantcomposition of claim 1 further comprising a carrier comprising gumacacia, xanthan gum, gum tragacanth, gum ghatti, and aloe vera gelextract; wherein the primary ingredients and the secondary ingredientsare present in the composition in a weight ratio of 1:2, with respect tothe carrier.
 12. The antioxidant composition of claim 11 wherein thecarrier comprises gum acacia, xanthan gum, gum tragacanth, gum ghatti,and aloe vera gel extract in a weight ratio of 30/30/20/19/1 percent,respectively.
 13. The antioxidant composition of claim 11 wherein thecomposition is roller-compacted.
 14. The antioxidant composition ofclaim 8 further comprising a carrier comprising gum acacia, xanthan gum,gum tragacanth, gum ghatti, and aloe vera gel extract; wherein thequercetin, the mixture of tocopherols, the grape skin extract, the greentea extract, and the bush plum are present in the composition in aweight ratio of 1:2 to 2:1, with respect to the carrier.
 15. Theantioxidant composition of claim 9 further comprising a carriercomprising gum acacia, xanthan gum, gum tragacanth, gum ghatti, and aloevera gel extract in a weight ratio of 30/30/20/19/1 percent,respectively; wherein the quercetin, the mixture of tocopherols, thegrape skin extract, the green tea extract, and the bush plum are presentin the composition in a weight ratio of 1:2 to 2:1 with respect to thecarrier and wherein the composition is roller-compacted.
 16. Anantioxidant composition comprising quercetin, a mixture of alpha, beta,delta, and gamma tocopherols, grape skin extract comprising 30-82%polyphenols, green tea extract comprising 35-95% polyphenols, bush plumpulp and skin comprising 5% vitamin C, and a carrier comprising gumacacia, xanthan gum, gum tragacanth, gum ghatti, and aloe vera gelextract; wherein the quercetin and the mixture of tocopherols areprimary ingredients and the primary ingredients are present in thecomposition in an amount of from 30% to 85% by weight in a weight ratioof from 40/60 to 90/10 percent; wherein the bush plum pulp and skin, thegreen tea extract, and the grape skin extract are secondary ingredientsand the secondary ingredients are present in the composition in anamount of from 15% to 70% by weight; wherein the grape skin extract andthe green tea extract are present in the composition in a weight ratioof from 60/40 to 80/20 percent; and wherein the quercetin, the mixtureof tocopherols, the grape skin extract, the green tea extract, and thebush plum pulp and skin are present in the composition in a weight ratioof 1:2 to 2:1, with respect to the carrier.